3 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
4 * Author: Inki Dae <inki.dae@samsung.com>
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; either version 2 of the License, or (at your
9 * option) any later version.
13 #include <drm/exynos_drm.h>
15 #include <linux/dma-mapping.h>
16 #include <linux/iommu.h>
17 #include <linux/kref.h>
19 #include <asm/dma-iommu.h>
21 #include "exynos_drm_drv.h"
22 #include "exynos_drm_iommu.h"
25 * drm_create_iommu_mapping - create a mapping structure
27 * @drm_dev: DRM device
29 int drm_create_iommu_mapping(struct drm_device *drm_dev)
31 struct dma_iommu_mapping *mapping = NULL;
32 struct exynos_drm_private *priv = drm_dev->dev_private;
33 struct device *dev = drm_dev->dev;
36 priv->da_start = EXYNOS_DEV_ADDR_START;
37 if (!priv->da_space_size)
38 priv->da_space_size = EXYNOS_DEV_ADDR_SIZE;
39 if (!priv->da_space_order)
40 priv->da_space_order = EXYNOS_DEV_ADDR_ORDER;
42 mapping = arm_iommu_create_mapping(&platform_bus_type, priv->da_start,
44 priv->da_space_order);
46 return PTR_ERR(mapping);
48 dev->dma_parms = devm_kzalloc(dev, sizeof(*dev->dma_parms),
50 dma_set_max_seg_size(dev, 0xffffffffu);
51 dev->archdata.mapping = mapping;
57 * drm_release_iommu_mapping - release iommu mapping structure
59 * @drm_dev: DRM device
61 * if mapping->kref becomes 0 then all things related to iommu mapping
64 void drm_release_iommu_mapping(struct drm_device *drm_dev)
66 struct device *dev = drm_dev->dev;
68 arm_iommu_release_mapping(dev->archdata.mapping);
72 * drm_iommu_attach_device- attach device to iommu mapping
74 * @drm_dev: DRM device
75 * @subdrv_dev: device to be attach
77 * This function should be called by sub drivers to attach it to iommu
80 int drm_iommu_attach_device(struct drm_device *drm_dev,
81 struct device *subdrv_dev)
83 struct device *dev = drm_dev->dev;
86 if (!dev->archdata.mapping) {
87 DRM_ERROR("iommu_mapping is null.\n");
91 subdrv_dev->dma_parms = devm_kzalloc(subdrv_dev,
92 sizeof(*subdrv_dev->dma_parms),
94 dma_set_max_seg_size(subdrv_dev, 0xffffffffu);
96 ret = arm_iommu_attach_device(subdrv_dev, dev->archdata.mapping);
98 DRM_DEBUG_KMS("failed iommu attach.\n");
103 * Set dma_ops to drm_device just one time.
105 * The dma mapping api needs device object and the api is used
106 * to allocate physial memory and map it with iommu table.
107 * If iommu attach succeeded, the sub driver would have dma_ops
108 * for iommu and also all sub drivers have same dma_ops.
110 if (!dev->archdata.dma_ops)
111 dev->archdata.dma_ops = subdrv_dev->archdata.dma_ops;
117 * drm_iommu_detach_device -detach device address space mapping from device
119 * @drm_dev: DRM device
120 * @subdrv_dev: device to be detached
122 * This function should be called by sub drivers to detach it from iommu
125 void drm_iommu_detach_device(struct drm_device *drm_dev,
126 struct device *subdrv_dev)
128 struct device *dev = drm_dev->dev;
129 struct dma_iommu_mapping *mapping = dev->archdata.mapping;
131 if (!mapping || !mapping->domain)
134 iommu_detach_device(mapping->domain, subdrv_dev);
135 drm_release_iommu_mapping(drm_dev);